抗双链DNA抗体检测策略研究

Study on Anti-dsDNA Antibody Detection Strategies

目的研究临床检测抗双链DNA抗体(anti-dsDNA)的最佳检测方案。方法将60例系统性红斑狼疮(SLE)血清,30例其他疾病对照组(ODC)血清和30例正常对照组(NC)血清样本同时进行线性免疫印迹法(LIA),绿蝇短膜虫间接免疫荧光实验(CLIFT),鲑鱼精子纯化抗原酶联免疫吸附实验(ELISA-Ⅰ)和胎牛胸腺纯化抗原酶联免疫吸附实验(ELISA-Ⅱ),检测血清标本中的anti-dsDNA。结果 LIA检测anti-dsDNA灵敏度为58.33%,CLIFT为56.67%,ELISA-Ⅰ51.67%,ELISA-Ⅱ73.33%;特异性分别为:LIA 71.67%,CLIFT100.00%,ELISA-Ⅰ93.33%,ELISA-Ⅱ86.67%。ELISA-Ⅰ与LIA、CLIFT比较,检测结果差异无统计学意义(P>0.05);ELISA-Ⅱ与LIA、CLIFT、ELISA-Ⅰ比较,检测结果差异具有统计学意义(P<0.01)。ROC分析显示ELISA-Ⅰ、ELISA-Ⅱ曲线下面积(AUC)分别为0.764和0.882(P<0.01);如采用ROC曲线的截断点(cut-off point),ELISA-Ⅰ的灵敏度和特异性为55.00%和91.67%,ELISA-Ⅱ为81.67%和83.33%;根据ROC曲线将特异性设置为95.00%时,ELISA-Ⅰ和ELISA-Ⅱ的灵敏度分别降低到48.33%和50.00%。结论 4种不同的antidsDNA检测试剂盒显示出不同的检测性能。CLIFT和ELISA均可用于anti-dsDNA的常规检测,由于ELISA具有良好的灵敏度,因此可作为anti-dsDNA的筛查实验;而CLIFT特异性最佳,可作为确证实验。无论临床实验室采取何种检测方法,针对anti-dsDNA的阳性检测结果,实验室工作人员应与临床医生始终保持足够的联系和沟通,并意识到临床实验室选择不同anti-dsDNA检测方法的灵敏度和特异性差异问题。

Objective To look for the optimum solution of anti-double-stranded-DNA （anti-dsDNA） antibodies detection. Methods To address the test feature of anti-dsDNA antibodies detection by different test methods, the performances of four immunoassays were compared. These included Line Immunoassay （LIA）, crithidia Luciliae Immunofluorescence test （CLIFT） and two enzyme-linked immunoassays （ELISA）. The sample set included 60 sera from systemic lupus erythematosus （SLE）; 30 from other diseases （ODC） and 30 from the normal control group（NC）. Results The sensitivity and specificity of these four assays were 58.33% and 71.67% （LIA）,56.67% and 100. 00% （CLIFT）, 51.67% and 93.33% （ ELISA-Ⅰ ）, 73.33% and 86.67% （ ELISA-Ⅱ ） respectively. There were no significant differences among LIA, CLIFT and ELISA-Ⅰ（P〉0.05）, but ELISA-Ⅱ showed the highest sensitivity （P〈0.01）. In ROC curve analysis, ELISA-Ⅰ and ELISA-Ⅱ showed AUC values of 0. 764 and 0. 882. When calculated by using the cut-off point of ROC curve, the sensitivity and specificity of ELISA- Ⅰ were 55.00% and 91.67% ; ELISA-Ⅱ were 81.67% and 83.33%. When evaluated by increasing the specificity values to 95.00%, the sensitivity of ELISA- I decreased to 48.33%, ELISA- 11 to 50.00%. Conclusion Four different assays showed various test features. Both CLIFT and ELISA are suitable for the routine test of anti- dsDNA antibodies in clinical laboratory. Due to the fact that ELISA showed the highest sensitivity, it can be used for screening purpose,CLIFT had the highest specificity, and can be used as a confirmation test. Regardless of the testing strategy among individual laboratories, clear communication with the clinical staff regarding the significance of a positive result is imperative. The laboratory and the clinician must both be aware of the sensitivity and specificity of each testing method used in the clinical laboratory.